A typical wireless lighting array comprises a large number of luminaires and a smaller number of switches and sensors. The luminaires are typically arranged in a regular structure in order that they provide an even level of background light. The individual elements of the lighting array communicate with one another over a wireless communication network, which is formed by an array of communication nodes. The wireless network provides a means for communication between neighbouring luminaires and for communication between the luminaires and the switches or sensors.
In order to commission such a lighting system, the array of luminaires is divided up into groups such that each group is controlled by a particular switch or sensor. For the lighting system to work correctly, it is important that the luminaires are divided up into sensible spatial control groupings so that each spatial group can be assigned to the closest appropriate switch or sensor. However, before the luminaires are assigned to spatial groups, it is necessary to ascertain their individual positions within the array.
It is known to derive position information for individual luminaires, within an array, using a topology generation algorithm. Such topology generation algorithms use range data, provided by the node network in the form of ranges between pairs of luminaires, to derive the relative positions of individual luminaires. The establishment of the positions of individual luminaires leads to an understanding of the structure of the lighting array.
Correctly understanding the structure of the lighting array is key to making the correct spatial groupings of luminaires. However, the range measurements between communication nodes, which are used to derive the structure of the array, are subject to error. Any such errors in the range measurements are propagated when calculating the relative positions of the individual luminaires, resulting in an erroneous understanding of the array's structure. Consequently, individual luminaires are not placed in the correct spatial group and, hence, are not controlled by the closest appropriate switch or sensor.